Hydraulic brake connection



March 22, 1938. c. H. |-m\1c:| EYl HYDRAULIC BRAKE CONNECTION Filed May e, 1957 mdf Patented Mar. 22 1938 UNITED STATES PATENT OFFICE l This invention relates to the connections that are between the actuating pedal and the .brake cylinders of four-wheel automobile, brake systems.

The object of the invention is to provide a simple and'inexpensive means that may be easily and quickly inserted by any mechanic in the uid connections of a new or .an old automobile, be-

tween a pedal operated master cylinder andthe brakecylinder of each wheel, which means on the failure of a brake at any wheel owing to leakage of. fluid, will isolate the brake of that wheel without interfering with the .electiveness Aof the brakes of the other wheels.

' the invention illustrated, by inserting in the uid connection between the brake cylinder of each I wheel and the master cylinder, a Cylinder containing a piston valve which at all times separates the fluid in the connection to the` brake cylinder from the fluid in the connection to the master cylinder, and which during normal proper action transmits fluid pressure from one connection -to the other, in one direction when the brake is to be applied and the opposite direction when fthe brake is to be released. However, if any leak'- age occurs from the brake cylinder or from the connection leading from the brake cylinder to the valve, the valve closes all communication with 30 that connection so that no iiuid can leak from y the master cylinder connection pastthe valve.

In the accompanying drawing Fig. v1 shows a central longitudinal section of a piston valve designed tc be used in accordance with theypresent invention.

y Fig. 2 is a diagrammatic view showing a piston valve located between the master cylinder and each of four wheels of an automobile.

Fig. 3 is a similar view showing a piston valve 40 arranged between the master cylinder and each l pair of wheels of an automobile.

The valve illustratedy comprises a cylinder I with its ends closed by heads 2. 3. Fitted closely in and movable longitudinally of the cylinder is a piston 4 with suitable lubricant grooves 5. Attached to one end of the pistonfis a cup-shaped packing 6, preferably rubber, and at the other end of the piston isA a cup-shaped packing 1, preferably rubber.`

' 'The head 2 has a nipple 8 which is designed to be connected with the duct 9 from themaster cylinder I 0. This head also has a nipple I I which can be vented to allow the escape of air as fluid is iilled into'this end of the cylinder. vA 'stern I2.

55 is threaded through the head 2 to provide an This object is attained inthe embodiment of adjustable stop for the piston whenA it is moved toward this head. A clamping nutl I 3 is threaded on the outer end of the stem for'holdingthe stem in the position to` which it is adjusted. Sur- `,rounding the stem, and exerting tension between the head 2 and the cup packing 'I is a spring I4. A nipple I5 is threaded through the head 3. This nipple is designed to be connected' with a duct I6 which communicates with a brake cylinder. .The inner end of this nipple has a ange I 1 which acts as a valve seat when the cup-packing 6 is forcedagainst it. A nut I8 is arranged to 'clamp this nipple in place after it has been properly adjusted. The head 3 has an air venting nipple I9 and a nipple 20 with a spring closed ball valve 2l through which iluid may be forced to fill this end of the cylinder.

in the fluid conduit betweenV the master cylinder I0 and the brake 22 at each of the four wheels 23,

cylinders. On release of the pedal the forces are reversed and the pistons return to normal position.

If at any time there is a leakage of fluid at a brake cylinder or in a connection between a brake.

cylinder and the valve that guards it, so that that brake will be ineiective, when the pedal is depressed the piston in that valve will be forced forward and its packing 6 will seatr against the iiangek I 'I and close the outflow nipple I5. `With the pressure reduced by leakage, the spring I4 holds the packing seated. The pistons iit closely in the cylinders and the 'cup packings are not only positioned to act most eiciently on the pistons but they eliminate liability of uid leaking from the master supply pastvthe pistons. However, should any such leakage occur fluid will not be able to pass .a seated cup packing and escape through the outlet to the leaky brake cylinder.

These valves, which are simple and cheap to One'of these piston -valves l may be connected manufacture and install, may be inserted in the connections during building of a new car, or the iiuid conduits-of a car already built may be easily `cui: and the valvesquickly connected Without special master cylinder is necessary, as there is no direct mechanical connection of the valves to the mechanism of the master cylinder, and no particular brakes are required.

The invention isz- 1. In an automobile hydraulic brake system a master cylinder containing fluid and a brake cylinder containing fluid, a valve having in one end an opening in fluid connection with the master cylinder and having in the opposite end an opening in uid connection with the brake cylinder` said valve containing a piston with one endl exposed to master cylinder pressure and the other end exposed to brake cylinder pressure, said piston at all times completely isolating iiuid communication from the master cylinder to the A brake cylinder but movable to transmit master cylinder pressure to the brake cylinder when theA cylinders are filled with fluid and movable to close the opening in Ailuid connection with the brake cylinder upon reduction of iluid pressure in the brake cylinder, and a spring thrusting against the piston in the direction of the master cylinder pressure for holding the piston closed upon reduction of iiuid pressure in the vbrake cylinder.

2. In an automobile hydraulic brake system a master cylinder containing uid and abrake cylinder containing fluid, a valve having at one end a head with yan opening in iluid connection with the master cylinder and having at the opposite end a head with an opening in uid connection with the brake cylinder, v.said valve containing a piston provided at one end with an. elastic cup cylinder pressure to the brake cylinder when the cylindersare iilled with fluid and movable to cause the latter cupfto close the opening in fluid connection with'the brake cylinder upon reduc-- tion of fluid-pressure in-the brake cylinder, and a spring thrusting against the former cup in the direction of the master cylinder pressure for holding the latter.cup closed upon reduction oi' pressure in the brake cylinder..y

3. In an automobile hydraulic brake system, a master cylinder containing fluid and a brake cylinder containing' uid, a valve having at one end a detachable head supporting a nipple with an opening in iiuid connection with the master cylinder and having at the opposite end a detachable head supporting a nipple with an opening in iiuid connection with the brake cylinder, said latter nipple being threaded through the latter head and having a ange at its inner end, saidvalve containingka piston that has one end exposed to master cylinder pressure and the other end exposed to brake cylinder pressure and is movable to transmit master cylinder pressure to the brake cylinder when the cylinders are illled with iluid and further movable to seat upon said flange and close the opening in the fluid connection with 'the brake cylinder upon leakagelot fluid from the brake cylinder, and a spring thrusting against the piston in the direction of master cylinder pressure for causing' the piston to remain seated upon said iiange upon reduction oi' fluid pressure in the brake cyl- A inder pressure to the brake cylinder when the" cylindersare illled with uid and further movable to cause the piston to seat upon said iiange and close the' opening in the iluid connection with the brake cylinder, upon leakage of iiuid from the brake cylinder, and a sprin'g surrounding said stop stem and thrusting against the pistonI in the direction of master cylinder pressure for causing the piston to remain seated upon said ilange upon reduction oi.' fluid pressure in the brake cylinder.

CHARLES H. HINCmiEY. 

